What are construction standards for underground pipelines to ensure safety at construction sites in Vietnam?

What are construction standards for underground pipelines to ensure safety at construction sites in Vietnam?

In Section 2.8.9 Subsection 2.8 Section 2 National technical regulation on safety in construction QCVN 18:2021/BXD promulgated together with Circular 16/2021/TT-BXD on construction standards for underground pipelines to ensure safety at construction sites as follows:

2.8.9.1 Before construction , it is necessary to carry out test drilling on the pipeline to confirm the presence of air pockets or groundwater.

2.8.9.2 Ventilation systems must be installed in underground pipelines.

2.8.9.3 In case the pipeline is installed in an area with groundwater , there must be an anti-flood door at the end of the pipeline.

2.8.9.4 There must be suitable means of communication, ensuring trust between people inside and outside the pipeline.

2.8.9.5 There must be a quick escape measure for workers to get out of the pipeline in case of an emergency.

2.8.9.6 Measures must be taken to rescue those in the pipeline when they are in danger and cannot move to a safe place by themselves.

What are standards for cofferdams, caissons and working in compressed air environment in order to ensure safety at construction sites in Vietnam?

In Section 2.9.1 Subsection 2.9 Section 2 National technical regulation on safety in construction QCVN 18:2021/BXD promulgated together with Circular 16/2021/TT-BXD on standards for cofferdams, caissons and working in compressed air environment in order to ensure safety at construction sites as follows:

2.9.1.1 For cofferdams, caissons, survey, design, construction, erection, inspection, testing (if the design is specified), inspection (if any upon request) by the competent authority), acceptance, monitoring, use, maintenance, dismantling (with cofferdams), archiving of records and documents in accordance with the provisions of the law on construction ( as applicable to construction works ) and the provisions of this regulation.

2.9.1.2 Cofferdams and caissons:

a) To be constructed, fabricated and installed according to the design, using materials of quality, suitability and durability (according to usage requirements);

b) Be fully equipped with equipment and take necessary precautions to ensure worker safety even in the event of water or other material spillage;

c) Arrange road access to the workplace must be safe for employees.

2.9.1.3 The fabrication, positioning, installation, repair and dismantling of the cofferdams, caissons be carried out under the direct supervision of a competent person.

NOTE: Competent persons include the construction and safety manager of the contractor and (or) the designer (when there is a problem related to the design) and the construction and safety supervisor of the owner (or EPC general contractor); experienced in cofferdams, caissons.

2.9.1.4 Only allow people to work in the cofferdams, caissons being checked and verified by an authorized person (see 2.9.1.3). Test results must be saved.

2.9.1.5 Employees working in a compressed air environment must be medically examined and confirmed to be suitable for the assigned work; training and clear instructions (with leaflet) on the mandatory precautions to be taken in relation to work performed in compressed air.

2.9.1.6 Only allow workers in accordance with the provisions of 2.9.1.5 to work in a compressed air environment under the constant supervision of a competent person (see 2.9.1.3) for activities and health conditions (physical and mental).

2.9.1.7 Do not allow anyone to work in an environment with a pressure exceeding 2.5 bar, except for those professionally trained for use in emergencies (e.g. performing rescue operations, incident handling) and have specialized industrial protection equipment.

2.9.1.8 For each shift, a record containing information on the time that the worker has worked in the compressed air compartment and the time of their depressurization must be kept.

2.9.1.9 If the air pressure at the workplace exceeds 1.0 bar, medical examination of workers must be carried out within 04 (four) weeks before assigning them to work.

2.9.1.10 Employees who work continuously in a compressed air environment with a pressure of less than 1.0 bar must be checked medically every two months and if the working environment has a higher pressure, the time The time between medical re-examination will be shorter.

2.9.1.11 An employee who has not worked in a compressed air environment for a period of 10 (ten) days or more, or due to illness, or other reasons must undergo a medical examination before being allowed to return to work. work again. These people must be arranged to work in a compressed air environment gradually (step by step, in ascending order).

2.9.1.12 For projects with employees working in a compressed air environment, the investor or the employer must ensure that there are always medical and rescue workers.

NOTE A site health worker is a doctor, nurse or first aid worker who is trained and experienced with the job and specialized medical equipment used in atmospheric environments. 

2.9.1.13 When an employee works in a compressed air environment with a pressure exceeding 1.0 bar, the employer must notify the hospital nearest to the workplace, the name and address (including number) telephone and other effective means of communication) of medical personnel performing medical supervision at the construction site.

2.9.1.14 Persons working in a compressed air environment with a pressure exceeding 1.0 bar must have an identification tag worn on their body to confirm that the person is authorized to work in a compressed air environment and has location information. of the pressurized chamber (medical lock) at the workplace.

NOTE The identification tag must clearly state that the person wearing the tag must be taken to a pressurized room and not to a hospital if he or she becomes ill.

2.9.1.15 Employers are responsible for arranging temporary rest houses (or rooms) with seats for employees working in a compressed air environment to rest after depressurization.

2.9.1.16 Do not allow any person who has never worked in a compressed air environment to enter a compressed air environment, unless they are in a man lock with an authorized person (see at 2.9.1.3) and have experience or medical personnel instructing them on appropriate actions (including handling of situations) during compression.

2.9.1.17 During pressurization, the equipment operator shall not increase the pressure by more than 0.25 bar until it is certain that no one feels discomfort; then the pressure is only allowed to rise at a rate not exceeding 0.5 bar per minute.

2.9.1.18 During the pressurization process, when any person feels uncomfortable, the pressurization must be stopped and the pressure must be gradually reduced.

Best Regards!